Vibration decoupling connector for exhaust systems

ABSTRACT

A vibration decoupling exhaust connector is provided having a flange for mounting the connector to a flange or housing surface of an exhaust system component, such as an exhaust manifold of an internal combustion engine. A liner tube is resiliently supported in the flange, by a vibration damping resilient metal mesh ring. A bellows is sealingly connected to the liner tube and the flange, in order to provide flexible sealing of the connector, for substantially precluding escape of exhaust gases from the joint when the connector is in place.

This application is a continuation-in-part of application Ser. No.08/986,105, filed Dec. 5, 1997, which is, in turn, acontinuation-in-part of application Ser. No. 08/838,601, filed Apr. 10,1997.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to connectors for joining the ends ofsuccessive lengths of pipe or conduit and/or connecting a pipe orconduit to a housing or other mounting surface wherein the connectionwill be exposed to axial, transverse and bending vibrations. Inparticular, the present invention relates two connectors for joiningpipes to one another or to other structures such as exhaust manifolds inexhaust systems for vehicles.

2. The Prior Art

It is well known that, in vehicle exhaust systems, the internalcombustion (i.c.) engines produce significant amounts of vibration inthe exhaust system. Operation of the motor at continuous speeds forprolonged periods of time can, especially, produce what are known asharmonic vibrations which can cause significant deflection in extendedlengths of exhaust pipe and at locations where such pipes are mounted tostructures such as brackets, engine manifolds and the like. Repeateddeflections and vibrations along the exhaust pipe system can, in turn,cause the structures to weaken with time and ultimately fail. Further,such harmonic vibrations can also be transmitted through the exhaustpipes to the mountings of the pipes, promoting the loosening of themountings, which can result in the sudden displacement of one or morecomponents of the exhaust system, with the potential for both personalinjury and equipment damage.

In addition to the vibrations caused by the operation of the engine ofthe vehicle, an exhaust system is also subjected to various tension,compression and bending forces which also arise during the operation ofthe vehicle. While individual exhaust system components could be madestronger and more massive to resist failure by fatigue, suchconstructions would be undesirable due to weight considerations.Further, by making individual elements stiffer, the vibrations aremerely transmitted throughout the exhaust system to the mounting orother components and are not reduced or eliminated. Accordingly, it isdesirable to isolate the exhaust system, or at least components of thesystem, from such vibrations and forces.

It is known that if the pipes of an exhaust system are divided andseparated by non-rigid connections, rather than being constructed ascontinuous extended lengths, the development of harmonic vibrations fromthe motor is precluded or reduced. Such non-rigid connections can beadvantageously employed to absorb other tension, compression and bendingforces, apart from and in addition to the motor vibration.

It is therefore desirable to provide a connector for joining a length ofexhaust pipe, to another pipe or to a mounting, such as an enginemanifold which connector joins the components in a non-rigid fashion andis capable of decoupling the consecutive pipes or other components toabsorb tension, compression and bending forces, as well as vibrationalforces, without transmitting them from one exhaust system component tothe next.

Typical prior art flexible connectors often require welds at both endsin order to achieve a strong, substantially fluid-type connectionbetween the connector and the other exhaust system components to whichthey are attached. It would be desirable to avoid the use of weldswhenever possible, as such welds take time to perform, adding to theinstallation time of the connector and increasing the overall assemblytime of the vehicle or apparatus to which they are being attached.

In addition, such welds are often difficult to place properly, oftenrequiring additional complexity in the construction of the flexibleconnector in order to provide working space for accomplishment of theweld. Still further, there is always a possibility of a small flaw inthe weld, leading to possible leakage of harmful exhaust gases, and/orthe introduction of a physical weakness in the structure of the flexibleconnector attachment, leading to the expenditure of additional time fordouble checking the quality of each weld being performed.

Also, welds are skill and labor intensive and add significant costs tosuch flexible connectors often amounting to a substantial percentage ofthe overall costs of the component.

Flexible exhaust system connectors, especially those which are used inconnecting the exhaust manifold of an engine to the "down pipe" leadingto the catalytic converter, are additionally under the constraint ofhaving to accommodate the vibration of the engine while at the same timehaving to be physically small in order to fit into the cramped space ofthe engine compartment. In the prior art, it has been known for theconnectors used in joining exhaust manifolds to the pipes leading to thecatalytic converter to take the form of ball joint type connectors,inasmuch as such ball joint type connectors typically have a relativelysmall envelope and can fit into tight spaces. However, ball jointconnectors are typically not completely sealed and can be prone to acertain amount of leakage when they are overly extended or compressed.In view of ever increasing constraints of the pollution levels whichinternal combustion engines are permitted to produce, as well as safetyconcerns regarding the leakage of exhaust gases in engine compartments,the use of such ball joint type connectors is becoming undesirable andmay become prescribed by law.

Accordingly, it is desirable to provide an alternative vibrationdecoupling exhaust system connector which has the functional advantagesof a ball joint type connector in that it can absorb or accommodatevibratory forces and can fit into a small envelope but is capable ofproviding more complete sealing and resistance to leakage of exhaustgases.

These and other objects of the invention will become apparent in view ofthe present specification including claims, and drawings.

SUMMARY OF THE INVENTION

The present invention comprises, in part, a flexible connector apparatusfor connecting first and second components of a fluid conduit system,such as an exhaust system for an internal combustion engine. Theapparatus comprises a bellows member, having an axis, first and secondends, and at least two substantially uniform convolutions disposedsubstantially adjacent the first of the two ends; and a flange member,positioned in circumferentially surrounding relationship to the bellowsmember, axially between the at least two substantially uniformconvolutions of the bellows member.

The flange member includes at least one attachment element, operablyassociated with the flange member and configured for attachment of theflange member to one of the first and second components of the fluidconduit system.

The attachment element further is configured to capture one of the atleast two substantially uniform convolutions axially between the flangemember and the one of the first and second components of the fluidconduit system, for forming, upon completed attachment of the flangemember to the one of the first and second components, a substantiallyfluid-tight weldless seal between one of the at least two substantiallyuniform convolutions of the bellows and the adjacent end of the bellowsmember, and the one of the first and second components.

The axially opposite end of the bellows member is operably configuredfor attachment at least indirectly to the other of the first and secondcomponents, for forming a substantially fluid-tight connectiontherewith, toward enabling the substantially fluid-tight transportationof fluid from the one of the first and second components, through theflexible connector apparatus, to the other of the first and secondcomponents.

The flexible connector apparatus further comprises, in one embodiment, aliner tube structure insertably received within the bellows member. Theliner tube structure, in turn, may comprise a first liner tube memberhaving a radially outwardly extending annular flange at one end thereof,the first liner tube member being insertably received in the first endof the bellows member, such that at least a portion of one of the atleast two substantially uniform convolutions is positioned axiallybetween the flange member and the radially outwardly extending annularflange member, such that upon capture of the convolution between theflange member and the one of the first and second components, theradially outwardly extending annular flange member is also capturedthereby; and a second liner tube member, telescopically engaged with thefirst liner tube member and insertably received within the bellowsmember, at a position distal to the first end of the bellows member,being operably configured for attachment at least indirectly to theother of the first and second components, for forming a substantiallyfluid-tight connection therewith, toward enabling the substantiallyfluid-tight transportation of fluid from the one of the first and secondcomponents, through the flexible connector apparatus, to the other ofthe first and second components.

A first substantially resilient spacer member is radially disposedbetween the telescopically engaged first and second liner tube members.Axially spaced first and second stop members, may be operably associatedwith the first and second liner tube members, respectively, for axiallyengaging the first spacer member therebetween, and limiting extensiveaxial movement of the first and second liner tube members relative toone another.

An end cap member may be provided, circumferentially surrounding aportion of the second end of the bellows member and a portion of thesecond liner tube member distal to the first liner tube member.

A second end cap member may be provided, circumferentially surrounding aportion of the first end of the bellows member and a portion of thefirst liner tube member distal to the second liner tube member, aportion of the second end cap member in turn being circumferentiallysurrounded by the flange member.

In an alternative embodiment of the invention, the bellows member isfabricated from at least two telescopically engaged tubular members, sothat at least an innermost one of the tubular members overlaps others ofthe tubular members and, at least at the end proximate the flangemember, extends axially beyond at least one other of the tubularmembers.

An end cap member may be provided, circumferentially surrounding aportion of the member, a portion of the end cap member in turn beingcircumferentially surrounded by the flange member.

In another embodiment of the invention, the convolution which isdisposed between the flange member and the proximate end of the memberis formed from a layer of no more than two telescopically engagedtubular members.

The present invention also comprises a method for manufacturing aflexible connector apparatus, for connecting first and second componentsof a fluid conduit system, such as an exhaust system for an internalcombustion engine, comprising the steps of:

forming a first tubular member, having two ends;

forming a flange member, having an aperture therethrough having aninside diameter which is substantially equal to but greater than anoutside diameter of the first tubular member;

configuring at least one attachment element on the flange member toenable attachment of the flange member to one of the first and secondcomponents;

inserting the first tubular member into the aperture of the flangemember, to a position proximate one of the two ends of the first tubularmember;

forming a plurality of at least two annular substantially uniformconvolutions in the first tubular member, each such convolution havingan outside diameter greater than the outside diameter of the firsttubular member,

subsequent to formation of the at least two substantially uniformconvolutions, the flange member being positioned between andsubstantially abutted by two of the at least two substantially uniformconvolutions.

In one embodiment of the method, the method further comprises the stepsof:

inserting a liner structure into the first tubular member afterformation of the at least two substantially uniform convolutions; and

mechanically connecting the liner structure to the first tubular member.

The step of inserting a liner structure further comprises the steps of:

forming an first liner tube member having a diameter which is less thanthe diameter of the first tubular member;

forming an second liner tube member having a diameter which is less thanthe diameter of the first tubular member and predominantly less than thediameter of the first liner tube member;

telescopically inserting the second liner tube member into the firstliner tube member, so that a portion of the first liner tube memberoverlaps a portion of the second liner tube member.

The step of inserting a liner structure may further comprise the stepof:

positioning at least a first substantially resilient spacer memberradially between the first liner tube member and the second liner tubemember.

The method may further comprise the step of:

preparing the end of the first tubular member, proximate the flangemember, so that, upon attachment of the flexible connector apparatus toone of the first and second components, one of the convolutions becomesentrapped and compressed between the flange member and the one of thefirst and second components, to form a substantially fluid-tight sealtherebetween, toward precluding escape of fluid therefrom.

Preferably, the step of inserting the first tubular member into theaperture of the flange member, to a position proximate one of the twoends of the first tubular member further comprises the step of:

inserting an end cap member over the first tubular member, a portion ofthe end cap member being radially enclosed by the first tubular memberand the flange member.

Alternatively, the method may further comprises the steps of:

forming one or more second tubular members, having a diameter less thanthe diameter of the first tubular member; and

inserting the one or more second tubular members into the first tubularmember, so that at least the first tubular member overlaps the one ormore tubular members, and at least at the end proximate the flangemember, extends axially beyond at least one of the one or more tubularmembers.

The step of forming a plurality of at least two substantially uniformconvolutions further comprises the step of:

forming the convolution which is to be disposed between the flangemember and the proximate end of the member from a layer of no more thantwo telescopically engaged tubular members.

In a further embodiment of the invention, the invention also comprises avibration decoupling connector apparatus, for connecting first andsecond components of a fluid conduit system, such as an exhaust systemfor an internal combustion engine. A mounting member is provided, havingan aperture therethrough for the passage of fluid, the aperture havingan inside surface, the mounting member being configured for attachmentto a structural member in a fluid transport system. A pipe member has atleast a first end region and a second end region.

A resilient flexible sealing member substantially surrounds at least aportion of the pipe member, and has two ends, a first of the two endsbeing operably connected to the first end region of the pipe member, asecond of the two ends being operably connected to the mounting member,at least a portion of the second of the two ends of the resilientflexible sealing member being received within the aperture in themounting member. An annular vibration damping member is radiallypositioned between a portion of the second end region of the pipemember, and a portion of the second end of the resilient flexiblesealing member.

Means axially position the annular vibration damping member, relative tothe portion of the second end region of the pipe member, the portion ofthe second end of the resilient flexible sealing member and the apertureof the mounting member, so that the annular vibration damping member isoperably and effectively positioned within the region formed by theaperture of the mounting member.

The second end region of the pipe member is disposed in vibrationabsorbing contact with the vibration damping member, for enablingrestricted relative axial, lateral and angular movement between the pipemember and the mounting member, when the mounting member is affixed to astructural member in a fluid transport system.

The resilient flexible sealing member is preferably positionedsubstantially against the inside surface of the aperture.

The means for axially positioning the annular vibration damping membercomprises a first flange member, extending radially outwardly from thesecond end region of the pipe member; and a second flange member,extending radially outwardly from the second end region of the pipemember. The first and second flange members are axially spaced from oneanother, with the annular vibration damping member being axiallyenclosed between the first and second flange members.

The means for axially positioning the annular vibration damping memberalternatively comprises a first flange member, extending radiallyoutwardly from the second end region of the pipe member. At least aportion of the first flange member is substantially enclosed within andengaged by portions of the annular vibration damping member.

The invention further comprises means for sealing the resilient sealingmember to a structural member in a fluid transport system. The means forsealing the resilient sealing member to a structural member in a fluidtransport system comprises a portion of the second end of the resilientflexible sealing member, extending axially beyond the mounting member,and operably configured to be positioned axially between the mountingmember and a structural member in a fluid transport system, and furtheroperably configured to substantially circumferentially surround a fluidtransport aperture in a structural member in a fluid transport system,so that when the mounting member is affixed to a structural member, asubstantially fluid-tight seal is established between the second end ofthe resilient flexible sealing member, and the structural member.

In a preferred embodiment of the invention, wherein the bellows memberhas at least two annular convolutions along its length, and the meansfor sealing the resilient sealing member to a structural member in afluid transport system comprises one of the at least two annularconvolutions being positioned axially beyond the mounting member, sothat when the mounting member is affixed to a structural member of afluid transport system, the one of the at least two convolutions becomescaptured and crushed between the mounting member and the structuralmember.

The annular vibration damping member preferably comprises a compressedmetal mesh ring. Alternatively, the annular vibration damping membercomprises a compressed ceramic mesh ring.

The invention further comprises an annular substantially rigid guardmember, operably connected to the first end region of the pipe member,and substantially surrounding the resilient flexible sealing member.

The invention also comprises a method for manufacturing a vibrationdecoupling connector apparatus, for connecting first and secondcomponents of a fluid conduit system, such as an exhaust system for aninternal combustion engine, comprising the steps of:

configuring a mounting member, with an aperture therethrough for thepassage of fluid, the aperture having an inside surface, for attachmentto a structural member in a fluid transport system;

substantially surrounding at least a portion of a pipe member, having atleast a first end region and a second end region, with a resilientflexible sealing member with two ends;

operably connecting a first of the two ends to the first end region ofthe pipe member;

operably connecting a second of the two ends to the mounting member, atleast a portion of the second of the two ends of the resilient flexiblesealing member being received within the aperture in the mountingmember;

radially positioning an annular vibration damping member a portion ofthe second end region of the pipe member, and a portion of the secondend of the resilient flexible sealing member;

axially positioning the annular vibration damping member, relative tothe portion of the second end region of the pipe member, the portion ofthe second end of the resilient flexible sealing member and the innersurface of the aperture of the mounting member, so that the annularvibration damping member is substantially circumferentially surroundedby the inside surface of the aperture of the mounting member,

disposing the second end region of the pipe member in vibrationabsorbing contact with the vibration damping member, for enablingrestricted relative axial, lateral and angular movement between the pipemember and the mounting member, when the mounting member is affixed to astructural member in a fluid transport system.

The method further comprises the step of positioning the resilientflexible sealing member substantially against the inside surface of theaperture.

The step of axially positioning the annular vibration damping membercomprises the steps of:

extending a first flange member, radially outwardly from the second endregion of the pipe member;

extending a second flange member, radially outwardly from the second endregion of the pipe member,

axially spacing the first and second flange members from one another,with the annular vibration damping member being axially enclosed betweenthe first and second flange members.

The step of axially positioning the annular vibration damping memberalternatively comprises the steps of:

extending a first flange member, radially outwardly from the second endregion of the pipe member,

substantially enclosing at least a portion of the first flange memberwithin and engaging the portion of the first flange member by portionsof the annular vibration damping member.

The method further comprises the step of:

sealing the resilient sealing member to a structural member in a fluidtransport system. The step of sealing the resilient sealing member to astructural member in a fluid transport system comprises the step of:

axially extending a portion of the second end of the resilient flexiblesealing member, beyond the mounting member, and operably configuring theportion of the second end of the resilient flexible sealing member to bepositioned axially between the mounting member and a structural memberin a fluid transport system, and further operably configuring theportion of the second end of the resilient flexible sealing member tosubstantially circumferentially surround a fluid transport aperture in astructural member in a fluid transport system, so that when the mountingmember is affixed to a structural member, a substantially fluid-tightseal is established between the second end of the resilient flexiblesealing member, and the structural member.

In the method according to this alternative embodiment of the invention,the resilient flexible sealing member comprises a bellows member havingat least two annular convolutions along its length, and the step ofsealing the resilient sealing member to a structural member in a fluidtransport system comprises the step of:

axially positioning one of the at least two annular convolutions beyondthe mounting member, so that when the mounting member is affixed to astructural member of a fluid transport system, the one of the at leasttwo convolutions becomes captured and crushed between the mountingmember and the structural member.

Preferably, in this method, the annular vibration damping membercomprises a compressed metal mesh ring. Alternatively, the annularvibration damping member comprises a compressed ceramic mesh ring.

The method alternatively further comprises the step of:

operably connecting an annular substantially rigid guard member to thefirst end region of the pipe member, and substantially surrounding theresilient flexible sealing member with the annular substantially rigidguard member.

In a still further embodiment of the invention, a vibration decouplingconnector apparatus, for connecting first and second components of afluid conduit system, such as an exhaust system for an internalcombustion engine, comprises a mounting member, having an aperturetherethrough for the passage of fluid, the mounting member beingconfigured for attachment to a structural member in a fluid transportsystem. A pipe member has at least a first end region and a second endregion. A resilient flexible sealing member substantially surrounds atleast a portion of the pipe member, and having two ends, a first of thetwo ends being operably connected to the first end region of the pipemember, a second of the two ends being operably connected to themounting member. An annular vibration damping member is radiallypositioned between a portion of the second end region of the pipemember, and a portion of the mounting member. Means are provided foraxially positioning the annular vibration damping member, relative tothe portion of the second end region of the pipe member and the apertureof the mounting member, so that the annular vibration damping member isoperably and effectively positioned within the region formed by theaperture of the mounting member. The second end region of the pipemember is disposed in vibration absorbing contact with the vibrationdamping member, for enabling restricted relative axial, lateral andangular movement between the pipe member and the mounting member, whenthe mounting member is affixed to a structural member in a fluidtransport system.

In yet another embodiment of the invention, the second end of theresilient sealing member extends at least partially into the aperture ofthe mounting member.

The present invention also comprises a vibration decoupling connectorapparatus, for connecting first and second components of a fluid conduitsystem, such as an exhaust system for an internal combustion engine.

A mounting member has an aperture therethrough for the passage of fluid.The aperture has an inside peripheral surface, and is configured forattachment to a structural member in a fluid transport system.

A liner tube member, having a first end and a second end, is insertablyreceived through the aperture of the mounting member, so that the firstend of the liner tube member is distal to the mounting member and thesecond end of the liner tube member is proximate to, and positioned onan opposite side of the mounting member from the first end. A flexibleresilient sealing member substantially surrounds at least a portion ofthe liner tube member and having two ends, a first of the two ends beingsealingly connected to the first end of the liner tube member, a secondof the two ends being sealingly connected to the mounting member,proximate to the aperture of the mounting member.

An annular vibration absorbing damping member circumferentiallysurrounds the second end of the liner tube member, a portion of thedamping member being radially positioned between a portion of thesurface of the aperture and a portion of the liner tube. A first axialface of the annular vibration absorbing damping member is disposed inaxially abutting contact, at least indirectly, with a face surface ofthe mounting member. The annular vibration absorbing damping memberoperably supports the liner tube, relative to the mounting member, sothat the liner tube may undergo restricted axial and angular movementrelative to the mounting member.

A peripheral lip on the second end of the liner tube member is operablyconfigured to insertingly receive a portion of the axial length of theannular vibration absorbing damping member, and axially abut a secondaxial face of the annular vibration absorbing damping member, positionedopposite the first axial face of the annular vibration absorbing dampingmember.

The resilient sealing member may be positioned substantially against theinside surface of the aperture.

The mounting member preferably comprises a substantially planar flangemember. The inside surface of the mounting member comprises twoportions, a first portion having a first inside diameter, proximate afirst axial face of the flange member and a second portion, having asecond inside diameter greater than the first inside diameter, proximatea second axial face of the flange member. The face surface which isbeing axially abutted, at least indirectly, by the annular vibrationabsorbing damping member, is disposed between the first and secondportions of the inside surface of the aperture of the mounting member.The face surface, the second portion of the inside surface of theaperture of the mounting member and a portion of the liner tube definean annular pocket.

The annular vibration damping member is partially received within theannular pocket.

In an alternative embodiment of the invention, a second annularvibration damping member is received within the annular pocket, and thefirst annular vibration damping member axially abuts the second annularvibration damping member.

At least of the first (or second, if provided) damping members isfabricated from compressed metal mesh material.

Preferably, the resilient sealing member comprises a bellows memberhaving at least two annular convolutions along its length.

The peripheral lip is operably configured to extend into an aperturedisposed in the structural member of the exhaust system to which themounting member is to be attached.

The resilient sealing member and the annular vibration absorbing dampingmember are preferably both disposed in axial compression, when theconnector is in a neutral state and not encountering compressive,tensile or bending forces.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation, in partial section, of a flexible connectorapparatus, according to one embodiment of the invention, prior toassembly to an exhaust manifold.

FIG. 2 is a side elevation, in partial section, of a flexible connectorapparatus, according to one embodiment of the invention, subsequent toassembly to an exhaust manifold.

FIG. 3 is an end elevation of a flange member suitable for use as acomponent of any of the embodiments of the flexible connector apparatusof the present invention.

FIG. 4 is a side elevation of the flange member of FIG. 3.

FIG. 5 is a side elevation, in partial section, of an inlet tube of aflexible connector apparatus according to the embodiment of FIG. 1 ofthe present invention.

FIG. 6 is a side elevation, in partial section, of an outlet tube of aflexible connector apparatus according to the embodiment of FIG. 1 ofthe present invention.

FIG. 7 is a side elevation, in section, of a mesh ring of a flexibleconnector apparatus according to the embodiment of FIG. 1 of the presentinvention.

FIG. 8 is a side elevation, in section, of an end cap of a flexibleconnector apparatus according to the embodiment of FIG. 1 of the presentinvention.

FIGS. 9-11 are schematic illustrations of steps in the process offorming a bellows for a flexible connector apparatus according to theembodiment of FIG. 1 of the present invention.

FIG. 12-15 are schematic illustrations of steps in the process ofassembling the inlet and outlet tubes for a flexible connector apparatusaccording to the embodiment of FIG. 1 of the present invention.

FIG. 16-17 are schematic illustrations of steps in the process ofassembling the bellows/flange member structure to the assembled inletand outlet tubes for a flexible connector apparatus according to theembodiment of FIG. 1 of the present invention.

FIG. 18a is a side elevation, in partial section, of a flexibleconnector apparatus, according to another embodiment of the invention,prior to assembly to an exhaust manifold.

FIG. 18b is an end elevation of a flange member suitable for use with aflexible connector apparatus of the embodiment of FIG. 18a.

FIG. 19 is a fragmentary side elevation, in section, of a flexibleconnector apparatus, according to still another embodiment of theinvention.

FIG. 20 is a fragmentary side elevation, in section, of a flexibleconnector apparatus, according to still yet another embodiment of theinvention.

FIG. 21 is a sectional view of an apparatus for forming the convolutionsin a tube, which has a flange member fitted thereon.

FIG. 22 is a sectional view of the apparatus of FIG. 21, after pressurehas been applied to the water within the tube to be formed.

FIG. 23 is a sectional view of the apparatus of FIG. 21-22, when theblade pairs are moved so as to enlarge the bulges into convolutions.

FIG. 24 is a perspective view of a modified convolution formingapparatus, configured for forming a plurality of bellows/flange memberunits at one time, which are then separated by severing of their commontube.

FIG. 25 is a side elevation, in section, of the apparatus of FIG. 24.

FIG. 26 is an end elevation of a convolution forming apparatus accordingto any of FIGS. 21-25, showing the pivoting action of the blades inunison, relative to one another.

FIG. 27 is a side elevation, in section, of a vibration decouplerapparatus according to an alternative embodiment of the invention.

FIG. 28 is an enlarged view of a portion of the vibration decouplerapparatus according to the embodiment of FIG. 27.

FIG. 29 is an end elevation of the vibration decoupler apparatus of FIG.27.

FIG. 30 is a side elevation, in section, of a vibration decouplerapparatus according to another alternative embodiment of the invention.

FIG. 31 is an enlarged view of a portion of the vibration decouplerapparatus according to the embodiment of FIG. 30.

FIG. 32 is an end elevation of the vibration decoupler apparatus of FIG.30.

FIG. 33 is an enlarged sectional view of a vibration decoupler apparatusaccording to another embodiment of the invention.

FIG. 34 is perspective exploded view of the components of the vibrationdecoupling connector according to one embodiment of the invention.

FIG. 35 is a side elevation, partially in section, of the connector ofFIG. 34.

FIG. 36 is a side elevation, partially in section, of the connectoraccording to an alternative embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

While this invention is susceptible of embodiment in many differentforms, there is shown herein in the drawings and will be described indetail several specific embodiments, with the understanding that thepresent disclosure is to be considered as an exemplification of theprinciples of the invention and is not intended to limit the inventionto the embodiments illustrated.

FIGS. 1 and 2 illustrate flexible connector 10 according to oneembodiment of the invention. Several of the components which make upflexible connector 10, are also shown individually in FIGS. 3-8, andinclude flange member 12 (having central aperture 14 and bolt holes 16),inlet tube 18 (having outwardly turned flange 20 and inwardly turnedbead 22), outlet tube 24 having outwardly turned bead 26, mesh rings 28and 30, end cap 32, and bellows 34. Mesh rings 28, 30 may be formed fromcompressed steel mesh, ceramic wool, or the like, according to knowntechniques, and may even be impregnated with materials such as graphite,vermiculite and/or other friction-reducing material. In a preferredembodiment of the invention, mesh rings 28 and 30 are substantiallyidentical.

Depending upon the requirements of the particular installationapplication, the flange may have a different shape, other than generallyrectangular, and/or may have fewer bolt holes. In addition, while meshring 28 will be present in typically all applications, in someembodiments mesh ring 30 may not be employed.

Bellows 34 is preferably formed according to the process illustrated inFIGS. 9-11. A piece of sheet metal material is rolled into a cylindricaltube 40 and welded. According to the requirements of the particularinstallation application, a second sheet of material may be formed intoa tube 42 having a slightly greater or lesser diameter and thentelescopically inserted into or fitted around tube 40 to form acomposite tube 44. Additional, smaller diameter tubes may besuccessively inserted, as well. If a number of layers are desired forthe bellows tube, as an alternative to using plural telescoping tubes,the bellows tube may be formed as a spiral coil, having a number ofturns. Other methods of providing multiple tube layers may also be used.

The composite tube 44 is then hydroformed, according to otherwise knowntechniques, to produce substantially uniform convolutions 46, and totalbellows structure 34. In typical hydroforming of a bellows, a piece oftube (actually two or more telescopically arranged tubes) are placedinto a hydroforming device, and plugged at their ends. A typicalhydroforming apparatus has a plurality of blades, set in pairs, whichpivot together like a set of jaws. In other hydroforming apparatus, thepairs of blades are arranged to close together in a non-pivoting linear(e.g., vertical or horizontal) motion, like the components of a press.Each blade of each pair will have a semicircular cutout, so that when apair of blades is closed around the tube, the cutouts form an aperturewhich will have a diameter slightly greater than the initial greatestoutside diameter of the unformed tube. After the several pairs of bladeshave closed around the tube, and been clamped into place, asubstantially incompressible fluid material, such as water is inlettedinto the tube. Slight axial pressure may be exerted on the ends of thetube, after the ends have been plugged, or extra water pressure may beexerted on an inlet end, prior to sealing. Since the water isessentially incompressible, the tube yields, bulging in the locationsbetween the spaced apart pairs of blades.

The pairs of blades are all interconnected and configured for axialmovement, in pairs. For example, the axially outermost blade pairs canbe moved, such as by a hydraulic cylinder, toward one end of the tube.The movement of the various blade pairs is coordinated, so that thereduction in the length of the spaces between the blade pairs isaccomplished in a uniform manner. Movement of the blades begins afterthe tube has been "bulged" after introduction of the water. The blades"grab" the tube bulges, forcing the bulges to become radially larger andaxially shorter, growing into the evenly spaced convolutions seen in thefinished product.

However, in prior art bellows hydroforming procedures and prior artbellows constructions, a simple sequence of uniform convolutions isformed. In the present invention, at a selected location on thecomposite tube, which would be otherwise between the last convolution 48at one end and the penultimate convolution 50 adjacent to the lastconvolution 48, a flange member 12 is fitted over composite tube 44,prior to the hydroforming step, to form bellows 34 and compositebellows/flange member structure 52. In order to accommodate the flangemember during the hydroforming step, one pair of blades, which wouldotherwise form the indentation between the last and penultimateconvolutions, is omitted or shifted aside.

During the hydroforming step, the portion of composite tube 44, which isencircled by flange member 12 will conform to fit against the innersurface of aperture 14.

The process of hydroforming is illustrated in a highly schematic mannerin FIGS. 21-26.

FIGS. 21-23 show an apparatus for forming a single bellows tube/flangemember combination. Tube 44, with flange member 12 is inserted into thedevice, the pairs of blades 80, 81 are closed, nose pieces 83, 84 areinserted into the ends of tube 44, and sealed so that no water canescape from between either of nose pieces 83, 84, and the tube. Someform of position holding device, such as a spacer member (not shown),will position the flange during the convolution formation process. Tube44 is then filled with water through one of the nose pieces, e.g. nosepiece 84. As pressure is applied to the column of water in the tube, theblades constrain portions of the tube. The unconstrained portions of thetube 44 bulge radially outwardly, slightly.

The blade pairs 80, 81 and the end block pairs 86, 87 are then moved, ina coordinated manner, to "squeeze" the bulges. One of nose pieces 83, 84is moved (see arrow, FIG. 23), to follow the corresponding end of thecontracting tube 44, and the convolutions are formed. The ends of tube44 which project beyond blocks 86, 87, are affixed, to prevent the endsof tube 44 from being pulled in toward the center of the apparatus, asthe blade pairs are moved. One method of affixing the ends 44 would beto swage the ends to create flares which will axially fix the ends (seedotted line in FIG. 22).

Spacers 94, 96 are provided on the blades and on the blocks,respectively, so that as axial pressure is placed, for example from theleft to the right on the end block, the convolutions begin to form.Since the blade pairs will move varying distances, those on the right,will have the least distance to move, and the corresponding convolutionswill form first, although all the convolutions will be formed during thesingle hydroforming process. Since the final spacing of the blades ismore or less uniform, as defined by the spacers, the final convolutionswill be more or less uniform, including those on both sides of theflange.

FIGS. 24, 25 illustrate an alternative construction of the convolutionforming device, in which several (e.g., 3) bellows tube/flange memberunits are formed, using a common tube. After forming of theconvolutions, and removal of the formed tube from the device, the tubeis cut into three separate sections, typically at the locations wherethe necks are formed by blocks 86. The spacers are omitted for clarityof illustration.

FIG. 26 illustrates the relative pivoting of the separate units of theblade and block pairs. When the pairs are closed, a latch or clamp 90 isused to hold the pairs in closed position, against the pressure exertedby the tube as a result of the water pressure.

While one general type of hydroforming is shown schematically anddescribed herein, other forming techniques may be used. However, thegeneral process described has the advantage of more or lesssimultaneously forming substantially uniform convolutions on either sideof a flange in a single manufacturing step, enhancing themanufacturability and reducing the cost of the overall component.

After the hydroformed bellows/flange member structure 52 is removed fromthe hydroforming machine, bellows/flange member structure 52 willtypically undergo various adjustments and finishing processes, in orderto prepare the structure 52 for installation.

The remaining neck of composite tube 44 (which usually has a length ofabout 0.625 inches) may be further processed, in one of the followingmethods, among others: a) complete removal from convolution 48; b)trimming to a length of about 0.030 inches, which might typically becrushed down during the process of attachment to the manifold; and c)rolling radially inwardly and around and back into the bellows. Excessneck is then trimmed from the opposite end of composite tube 44.

Inlet tube 18, outlet tube 24, and mesh rings 28, 30 are assembledaccording to the procedure shown in FIGS. 12-15. First, mesh ring 28 isinserted into inlet tube 18, and fitted against bead 22. Preferably, theouter diameter of mesh ring 28 is such that there is a slightly forcedfit between mesh ring 28 and the inner surface of inlet tube 18. Next,outlet tube 24 is inserted into inlet tube 18 (from the right to left,the direction of the arrow, as seen in FIG. 13). Mesh ring 28 therebybecomes axially enclosed by beads 22 and 26.

Optional mesh ring 30 may then be fitted onto outlet tube 24, again,preferably with a slightly forced fit, until it abuts bead 22. Then, theportion of outlet tube 24, which is downstream of mesh ring 30, istypically expanded outwardly, such as by swaging, to an increaseddiameter, as shown in FIGS. 1, 2 and 15. The assembled components formliner tube structure 54.

In order to improve the fluid dynamics and reduce possible noise whichmay be created at the leading edge of outlet tube 24, the liner tubestructure 24 may be provided with a shroud 92, shown in phantom in FIG.17, which would extend radially inwardly from the inner surface of inlettube 18, to help smooth the flow of fluid through the flexibleconnector.

The final assembly of bellows/flange member structure 52 and liner tubestructure 54, to form flexible connector 10, prior to its subsequentinstallation to another component, such as an exhaust manifold, is shownin FIGS. 16-17. Liner tube structure 54, comprising inlet tube 18,outlet tube 24, and mesh rings 28, 30, is inserted into bellows/flangemember structure 52. Thereafter, end cap 32 is fitted onto the free endof the bellows/flange member structure 52, and forcibly sized radiallyonto the overlapping bellows 34 and outlet tube 24, to form a snugmechanical connection between outlet tube 24 and the bellows 34, at 56.One function of end cap 32 is to provide some protection to bellows 34against externally directed abrasion or moving objects, which coulddamage or even puncture the bellows.

Although a two-piece (inlet tube/outlet tube) liner is shown in theembodiment of FIGS. 1-17, other kinds of liner structure, within thebellows tube, can be employed, if desired. Other examples include, butare not limited to, a three-piece liner (two end tubes connected by athird outer or inner tube overlapping or overlapped by the two endtubes), a single piece of straight tube, a metal wire braided sleeve(often used for acoustic purposes and/or to limit the amount ofextension of the bellows), or a spiral wound tube, all of whichseparately are known in the art. Since these other kinds of linerstructures are inserted after formation of the bellows/flange structure,the assembly after formation of the liner, is substantially the same aspreviously described.

In addition, the beads 22, 24, which are shown to be 90° turns of theends of the liner tubes, may be substituted with flanges turned agreater or lesser amount, for example in the range from 45° to a full180° turn, or with annular rings welded onto the ends of the liner tubesor the like, or omitted altogether.

Alternative embodiments may have a flange at both ends of the bellowsstructure. This may readily be accomplished by placement of flanges nearopposite ends of the unformed bellows tube, and formation of theconvolutions in the manner discussed previously, using a suitablyconfigured convolution formation set-up, followed by insertion of aliner structure according to the needs of the particular application.

FIG. 2 illustrates the final assembly procedure, during which theflexible connector apparatus 10 is affixed to another exhaust vehiclecomponent, in this case, an exhaust manifold 58. Annular depression 59,which will have a depth which preferably will be approximately the sameas or slightly less than the thickness of flange 20 and which will havea diameter which will be at least as great as or slightly larger thanthat of flange 20, will be formed into exhaust manifold 58, either aspart of the original manufacturing process for manifold 58, or as alater machining step. Flexible connector apparatus 10 is affixed, suchas by bolts (not shown) through bolt holes 16 which will mate withcorresponding blind bolt holes (not shown) in exhaust manifold 58. Otherforms of fastening may be employed, if desired.

Alternatively, depression 59 could be placed in the opposing face offlange 12. In that case, it is important that the diameter of thedepression 59 is less than the diameter of convolution 48, so that theseal can be formed.

As the bolts are tightened down, for example, to the degree of tightnesswhich would be used in prior art coupler installations using gaskets,convolution 48 will become substantially completely flattened betweenexhaust manifold 58 and flange member 12, until seals are formed betweenflattened convolution 48 and exhaust manifold 58, and between flangemember 12 and flattened convolution 48 of bellows 34, respectively,which are substantially more effective in terms of fluid tightness, andmore simply obtained than prior art connector constructions, all withoutthe need for a separate gasket component. At the opposite end offlexible connector apparatus 10, if a fluid tight connection has beenformed between bellows 34 and outlet tube 24 by the sizing of end cap32, then outlet tube 24 is simply connected, typically by a simple weldor braze, to the downstream exhaust system component (not shown). If nofluid tight seal has been formed between outlet tube 24 and bellows 34,then such a seal is formed at the time of connection to the downstreamexhaust system component, using conventional assembly techniques.

If desired, the last convolution on apparatus 10 may be pre-compressed,prior to mounting to the exhaust manifold or other component to which itis being attached.

The embodiment of FIGS. 1-17 is shown having a liner tube structure, inwhich the inlet tube 18 has a greater diameter than, and insertablyreceives, outlet tube 24. It is understood that, if desired by therequirements of the particular installation application, the relativeorientations could be reversed, while still being within the scope ofthe present invention. That is, the inlet tube could be provided with alesser diameter, and be insertably received within, the outlet tube,with the inlet tube still being provided with a flange 20, as in theillustrated embodiments.

In addition, it is to be understood that the entire apparatus 10, which,as shown in FIGS. 1-17 is intended to be connected, for example, to anexhaust manifold, in which the flow of fluid is from right to left (inFIG. 2), could be installed in the reversed orientation, for example, tothe inlet of a muffler, in which case, the inlet tube would actually bethe outlet, and the flow through the apparatus would be from left toright, as the apparatus is seen in FIG. 2.

The flexible connector apparatus of the present invention provides asubstantially fluid-tight seal at the interface between the bellows andthe exhaust manifold, without the need for a weld or braze. In addition,such a connection can be made, if desired, without the need for apacking or seal positioned between the bellows and any clamping device,such as the flange member, and the surface of the exhaust manifold towhich the flexible connector is being attached. This enables theconnection to the exhaust manifold to be accomplished more quickly, moresimply, and less expensively, than in prior art flexible connectorconstructions.

In addition, in prior art flexible connector constructions, instead of aradially extending flange at the end of the inlet tube, only a necktypically would be provided which would have to have a substantialthickness, in order to accommodate the weld or braze which wouldtypically be used to connect the tube to the flange. Usually the weldingprocess would result in warping of the flange, which, in turn, wouldrequire the use of a gasket, to enhance the sealing of the connection.The present invention permits the inlet tube end and flange to be muchsmaller and thinner, since the material no longer has to be sized toaccommodate a weld. The invention also obviates the need for a sealinggasket.

In the embodiment of FIGS. 1-17, the inlet and outlet tubes, are linertubes, serving to thermally insulate the bellows from the exhaust gases.The inlet and outlet liner tubes also serve to isolate the bellowschemically from the corrosive exhaust gases. The inlet and outlet tubes,and mesh members, in cooperation with the bellows, accommodates axialextension and compression of the flexible connector apparatus, resultingfrom relative movement of the exhaust manifold (or other upstreamcomponent) and the downstream component (such as a tailpipe structure).The mesh members serve to provide resilient absorption of shock andvibration which might otherwise occur during over-compression andover-extension of the connector apparatus. In addition, the mesh ringsaid in dampening and decoupling lateral vibrations in the exhaustsystem. In addition, the inlet and outlet tubes and the spacer radiallyin between, provide support for the flexible connector structure.

In some applications, it may be desirable to provide a flexibleconnector construction, which is substantially self-supporting, as thatterm is understood by those of ordinary skill in the art (i.e., noadditional support for the connector for some stated number of tubediameters' distance from the connection to the exhaust manifold), butwhich eliminates the need for the inlet and outlet tubes, which, whileadding to the strength and load-carrying capacity of the flexibleconnector apparatus, simultaneously add to the flexible connectorapparatus' weight, cost and complexity. Such structure may not bedesirable or particularly advantageous in situations where weight orcost are critical or where available installation space is at a premium.

Such an alternative flexible connector apparatus 60 of the invention isshown in FIGS. 18a and 18b. The inlet and outlet tubes, and the meshrings are omitted. Bellows 62 is preferably formed from a plurality (2or more, 3, preferably) of layers of tube material, which may betelescoped, closely fitted tubes, or if a number of layers are desiredfor the bellows tube, as an alternative to using plural telescopingtubes, the bellows tube may be formed as a spiral coil, having a numberof turns. Other methods of providing multiple tube layers may also beused. A tube having a single thick layer could be used if desired insome applications. The formation of the bellows, with the flange member64, axially enclosed by convolutions 66 and 68, is accomplished byhydroforming techniques, substantially the same as those employed withrespect to the embodiment of FIGS. 1-17, in that flange member 64 isslipped onto the unformed tubes, prior to formation of at least theendmost convolution 68.

Not all of the "plies" of tubes forming the bellows 62 will becoextensive. While all of the plies may have aligned ends at the"downstream" end of flexible connector apparatus 60 (as illustrated), atthe upstream end (i.e., adjacent the flange member location), the end(s)of the radially innermost tube or tubes stop to form a cylindrical neck72, which is surrounded by the flange member 64. The innermost ply ortube 70 (or possibly the two innermost plies or tubes) proceed(s)upstream to form convolution 68. That is, the end convolution adjacentthe flange will be made from, typically, one (or more) fewer plies thanthe remaining convolutions, and the plies which make up the endconvolution will be the innermost one or two plies (although in theinstance of a tube having more than three plies, the numbers of plieswhich are shortened and the number which make up the last convolutionmay be varied). The reduction in the number of plies permits a strongbellows-only connector structure to be created, but still permits theflattening of the last convolution to provide the sealing between theflange, the convolution and the component to which the coupling is beingattached.

While it is preferred that at least the innermost ply form the endmostconvolution, the other plies if any of the endmost convolutionpreferably are the next adjacent plies, though others may be used.

The mounting of flexible connector apparatus 60 to an exhaust manifold(such as manifold 58 from the previous embodiment, minus the annulardepression 59) is similarly accomplished by bolting down flange member64 to an exhaust manifold or other structure having bolt holes alignablewith bolt holes 63 of flange member 64, and an aperture alignable withcentral aperture 65, of flange member 64.

The multi-ply bellows 62 of the flexible connector apparatus of FIG. 18aand 18b provides accommodation of extension, compression, and lateralmovements, with a substantially self-supporting feature arising from theincreased stiffening of the bellows structure, all without theadditional cost, complexity and weight of the inlet and outlet tubeliner structure of the prior embodiment.

Although not specifically illustrated, it is understood that theembodiment of FIGS. 1-17 can also be constructed having a bellowsfabricated from more than two telescoped tubes, and having an endconstruction, in which the end convolution adjacent the flange has fewerplies than the remaining convolutions.

FIG. 19 shows another alternative embodiment of the invention, which issubstantially similar to the embodiment of FIGS. 1-17, and whereinelements having functions and structures similar to that of likeelements in the first embodiment are provided with like referencenumerals, augmented by a prime ('). As it is understood that theapparatus of FIG. 19 is symmetrical about a central axis designatedC_(L), only the "upper" half of the flexible connector apparatus 10' isshown, in section.

Apparatus 10' is substantially identical to apparatus 10, both instructure, and in method of fabrication, except that an upstream end cap72 is provided, for giving some protection to the exterior of bellows34'. A cylindrical portion 74 of end cap 72 is captured between flangemember 12' and bellows 34', when the convolutions 48' and 50' of bellows34' are formed by the previously described hydroforming process.Typically the lesser diameter "neck" of end cap 72 will have an axiallength which is less than the thickness of flange member 12', so that itwill not extend entirely to convolution 48'. Once end cap 72 has beenpositioned, and bellows 34' formed, the remainder of the formation andassembly process for flexible connector apparatus 10' is the same asdescribed with respect to apparatus 10. End cap 72 provides protectionfor the bellows, and also provides lateral support for the bellowsitself, as described in further detail with respect to the followingembodiment.

FIG. 20 shows another alternative embodiment of the invention, which issubstantially similar to the embodiment of FIG. 18a and 18b, and whereinelements having functions and structures similar to that of likeelements in the first embodiment are provide with like referencenumerals, augmented by a prime ('). As it is understood that theapparatus of FIG. 20 is symmetrical about a central axis designatedC_(L), only the "upper" half of the flexible connector apparatus 60' isshown, in section.

Apparatus 60' is substantially identical to apparatus 60, both instructure, and in method of fabrication, except that an upstream end cap72' is provided, for giving some protection to the exterior of bellows62'. A cylindrical portion 74' of end cap 72' is captured between flangemember 64' and bellows 62', when the convolutions 66' and 68' of bellows62' are formed by the previously described hydroforming process.Typically, the neck portion of end cap 72' will have an axial lengthwhich is less than the thickness of flange member 64', so that it willnot extend entirely to convolution 68'. Once end cap 72' has beenpositioned, and bellows 62' formed, the remainder of the formation andassembly process for flexible connector apparatus 60' is the same asdescribed with respect to apparatus 60.

End cap 72', as discussed with respect to the other embodiments,provides external protection for the bellows convolutions in thevicinity of the ends of the bellows. In addition, and particularly withrespect to the bellows-only embodiment, the end cap(s) provide lateralsupport for the flexible connector apparatus. Especially in thebellows-only embodiment, the portion of the bellows (particularly thesmaller diameter portion or "core") nearest the ends can become exposedto substantial bending forces, which could lead to over-bending of thebellows, leading in turn to permanent excessive deformation and/orfatigue failure from repeated extreme bending. Accordingly, the end capprovides a limit to the amount of bending that the bellows can undergo.

In some embodiments, the diameter of the convolutions and the shape ofthe end caps will be established so that upon installation, the bellowswill have a compressive preload, so that endmost convolutions will beprompted into contact, at locations not at the greatest diameter, to theinner surface of the end caps, to provide further support for theflexible connector apparatus. In addition, the preloading of the bellowsconvolution against the end cap(s) prevents "buzzing" or rattling whichmight otherwise occur, during operation of the machine to which theflexible connector apparatus is attached.

In alternative embodiments of the invention, a braided metal sleeve,such as are known in the art, may be substituted for or used in additionto the end cap(s) 72, 72'. The placement of such a metal braid wouldoccur after the formation of the convolutions, including thosesurrounding the flange.

In a further alternative embodiment of the invention (FIGS. 27-29), pipe100 has a narrowed inlet end 105 which has an outer diameter which isless than the inner diameter of aperture 110 of flange plate 115. Theinner surface of aperture 110 has an L-shaped configuration, with alarger diameter portion and a radially inwardly extending lip 120. Abellows 125 is affixed at a downstream end 130 to pipe 100.

The upstream end 135 of bellows 125 is swaged radially outwardly toconform to the inner surface of aperture 110. In a preferred embodimentof the invention, the bellows 125 is formed, such as by hydroforming, tobe integral with flange plate 115, in a manner similar to that describedwith the prior embodiments. Instead of the flange plate having a simplecylindrical aperture, the aperture has an L-shaped cross-sectionalcontour, as illustrated. In this way, the bellows will conform closelyto the inside surface of the aperture.

As shown in greater detail in FIG. 28, end 135 of bellows 125 closelyconforms to lip 120. At the extreme tip of end 135, a final convolution140 is provided which is axially flattened, when flange plate 115 isbolted down against manifold 145, to provide a substantially gas-tightseal between manifold 145 and flange plate 115, without requiringwelding or the use of a gasket, such as are known in the art.

A mesh ring 150, which may be metal or ceramic mesh, the composition andphysical structure of which may be otherwise conventional, is positionedradially between the end 135 of bellows 125 and the outer surface ofpipe end 105. An outward turning 155, and an annular flange 160, whichmay be welded or otherwise affixed to pipe end 105 axially station meshring 150. As an alternative to affixing a separate piece of material topipe end 105, to form flange 160, a radially outwardly projecting bumpor ridge (not shown) may be provided. As a further alternative, acircumferentially extending, radial contraction or pocket may be formedin pipe end 105, which may serve to axially restrain the mesh ring. Inaddition, lip 120 also serves to preclude axial movement of the meshring. A shroud 165, which preferably will be a substantially rigidmetallic structure, may be provided, attached to pipe 100 over thedownstream end of bellows 125, to protect bellows 125.

Depending upon the preloading which is to be imposed upon the connector,in actual installation, the construction may vary slightly. For example,if the connector is always to be in compression (though in varyingdegrees), then outward turning 155 may not be necessary and may beomitted. Conversely, if the connector is always going to be in tension(though in varying degrees), then flange 160 may not be necessary andmay be omitted. If the connector will have a neutral restingconfiguration, or one which is slightly compressed, but may cross intotension, then the configuration of FIGS. 27-29 will be preferred.

In an alternative embodiment of the invention, instead of providingflange 160, and bracketing mesh ring 150, the turning 155' is provided.See FIGS. 30-32. The pipe end 105 is manufactured into the mesh ringduring the mesh ring manufacturing process. Specifically, prior to thefinal compression of the mesh ring, when the mesh material is stillrelatively loose, the already flared end 155' of the pipe 100 is pressedinto the mesh material. The mesh is then compressed around the flaredend, to tightly grip and adhere to the metal mesh. The remainingelements of the alternative construction of FIGS. 30-32 are preferablythe same as in the embodiment of FIGS. 27-29. In the embodiment of FIGS.30-32, the extreme end of bellows 125 is provided with a finalconvolution 140, which is axially flattened, when flange plate 115 isbolted down against manifold 145, to provide a substantially gas-tightseal between manifold 145 and flange plate 115, without requiringwelding or the use of a gasket, such as are known in the art.

In each of the foregoing embodiments, a mesh ring position holder may befitted into the tube prior to hydroforming of the bellows.Alternatively, since the final convolution may be a different diameterand configuration than the other convolutions of the bellows, the meshring insertion and formation of the final convolution may take placeafter formation of the bellows. The semi-finished bellows may beprovided with an elongated cylindrical end section, to accommodate theflange plate and the final convolution. The formation of the surfacesconforming to the inside surface of the aperture of the flange plate,and the formation of the final convolution, may be accomplished by amethod such as the insertion and rotation of a mandrel in thecylindrical end of the bellows, after which, the mesh ring may beinserted. Alternatively, the bellows itself may end in an out-turnedVan-Stone for utilization with a conventional sealing gasket.

It is not strictly necessary that the mesh ring fit with a high degreeof radial tightness, into the bellows, or that the bellows, in turn, fittightly into the contoured inside surface of the aperture of the flangeplate. Even after the formation of the bellows and the portionsconforming to the inside of the flange plate aperture and the finalconvolution, the fit between the mesh ring, bellows and flange plate,may have some looseness. As can be seen in FIGS. 28 and 31 (and 33 asdescribed hereinafter), the mesh ring is thicker, in its axialdimension, than the axial depth of the notch or recess formed byaperture 110 and lip 120. Accordingly, when flange plate 115 istightened down against manifold 145, the mesh ring becomes axiallycrushed, and clamped between the manifold and lip 120, with a positiveaxial compressive load. Some radial expansion, both inwardly andoutwardly, of the mesh ring, may occur.

Alternatively, the fit between the mesh ring and the adjacent insidesurface of the bellows, and/or between the bellows and the insidesurface of the aperture of the flange plate may be relatively snug. Anyrelative movement of the pipe end, relative to the flange plate, maypreferably be accommodated by the resilient flexibility of the mesh ringitself, and not by gross movement of the ring relative to the othercomponents.

Still another embodiment of the invention is shown in FIG. 33. In theapparatus 200 of FIG. 33, the bellows 205 does not extend throughaperture 210 of flange plate 215. Pipe end 105 may be identical to pipeend 105 of FIGS. 27-29, including turning 155. Flange 160 may also beprovided, which, as in the embodiment of FIGS. 27-29, is welded to pipeend 105, at 220. Bellows 205 ends in a radially outwardly extendingannular lip 225, which preferably may be affixed to flange plate 215 byweld 230. Mesh ring 235 may be constructed in substantially the samemanner as the mesh ring of the embodiment of FIGS. 27-29, but is notradially surrounded by the end of the bellows. Accordingly, since thereis no crushed bellows convolution to form a seal between flange plate215 and manifold 240, a gasket 245, such as are known in the art, ispositioned between flange plate 215 and manifold 240.

In this embodiment, the bellows may be formed by any suitable method,including hydroforming. Hydroforming, while a preferred method, is notrequired, since the bellows does not pass into or through the aperturein the flange plate. The bellows simply needs to be formed with asuitable amount of material left as a cylindrical neck, which may betrimmed as necessary, and the required radially extending annular lip225 can be formed.

In a still further alternative embodiment, the bellows may be formed sothat the end of the bellows enters into, stops within, but does not passcompletely through the aperture in the flange plate. In this embodiment(not shown), the end of the bellows would be affixed to the insidesurface of the flange plate, such as by welding. A gasket would still beneeded in order to provide a seal between the manifold and the flangeplate.

In each of the embodiments of FIGS. 27-33, the bellows, as discussedwith respect to the prior embodiments, may be formed from multiple pliesof material, in a manner substantially identical to that described withrespect to the embodiments of FIGS. 1-26. Although the bellows may beformed, such that the portion of the bellows which passes through theflange plate and forms the crushed bellows seal, may have one or morefewer layers than the majority of the bellows structure, alternatively,the bellows in all of the foregoing embodiments may be formed in such amanner that the same number of layers are present along the entirelength of the bellows.

FIGS. 34-36 illustrate two further alternative embodiments of theinvention.

FIGS. 34 and 35 illustrate the vibration decoupling connector accordingto one embodiment of the invention. Connector 310 includes a bellows312, a flange 314, a mesh ring 316 and a liner tube 318. All of thesecomponents are contemplated as being fabricated from 300- or 400-seriesstainless steel, though other materials may be used, as may be dictatedby the requirements of the particular environment for which theconnector is being fabricated.

Bellows 312 may be formed from one or more plies of metal material whichwas formed into a multiple convolution bellows by any suitabletechnique, such as by hydroforming or the like. While three convolutionsare shown in the figures for ease of illustration, it is understood thata greater or lesser number of convolutions may be formed in the bellowsas may be required by the circumstances of the particular application inwhich the connector 310 will be used. For example, if a greater numberof convolutions (e.g., 5), are provided, the convolutions would becloser together. Using a greater number of convolutions has the effectof increasing the endurance life of the component since there are moreconvolutions over which to spread the bending and axial compressive andtension forces.

Flange 314 is preferably stamped from a single piece of material and hasa central aperture 320 and two smaller apertures 322 and 324 which willbe used to connect the connector to a mating flange or to a housingstructure using machine screws in a known manner. Aperture 320 isstepped with a larger diameter portion 326 and a small diameter portion328.

Mesh ring 316 is formed from braided and compressed metal wire. Suchmetal mesh rings, as such, are known and have been employed in exhaustsystem connectors in prior art exhaust system connectors. Metal meshring 316, for example, is an annular structure which has a axial lengthL which is greater than the radial thickness T. The resilience andcompressibility of mesh ring 16 depend upon two factors, the density ofthe ring (the weight of the ring as a percentage of the weight of asolid metal ring of the same dimensions) and the diameter of the wire.According to one embodiment of the invention, the mesh ring 316 willhave a density of 32% and employ a 0.009" diameter wire. Mesh rings ofthat construction may be obtained from ACS Industries of Woonsocket,Rhode Island. One of ordinary skill in the art having the presentdisclosure before them will be able to modify the characteristics of themesh ring by varying one or both of these values, to obtain mesh ringshaving greater or lesser amounts of resilience, and greater or lesseramounts of compressibility, without undue experimentation.

Liner tube 318 includes an elongated cylindrical portion 330 and aradially outwardly turned lip 332. The outer diameter of the cylindricalportion 330 is slightly less than the inner diameter of the portion 328of aperture 320 of flange 314. The inner diameter of mesh ring 316 willbe approximately the same as the outer diameter of cylindrical portion330 so that there will be a slight friction fit between mesh ring 316and cylindrical portion 330 of liner 318. The inner diameter of lip 332is approximately the same as the outer diameter of mesh ring 316 so thatmesh ring will fit with a slightly forced fit into the space between lip332 and cylindrical portion of liner tube 318. The depth of the spacebetween lip 332 and cylindrical portion 330 is less than the axiallength L of mesh ring 316 so that when mesh ring 316 is fitted into thegroove between lip 332 and cylindrical portion 330, a substantialportion of mesh ring 316 extends axially out of the groove.

Vibration decoupling connector 310 is illustrated in its assembled formin half sectional view of FIG. 35. The assembly of connector 310 may beaccomplished in the following manner. Mesh ring 316 is slid overcylindrical portion 330 of liner 318 and into the groove between lip 332and cylindrical portion 330. Then, the assembled liner tube and meshring are inserted into aperture 320 of flange 314 so that the mesh ring316 is received in the larger diameter portion 326 of flange 320. Then,bellows 312 is slid over the end of liner tube 318 which projects out ofthe far side of flange 314, with the neck 334 of bellows 312 fittinginto the smaller diameter portion 328 of aperture 320. Preferably, neck334 has a diameter which is less than the diameter of aperture portion328, so that a clearance is provided, to enable some pivoting movementof the neck 334 relative to the flange.

A weld 329 is provided, between the flange 314 and the bellows 312. Theweld 329 runs around the entire periphery of aperture portion 326, nearthe corner formed by the aperture and the face of the flange.Preferably, the weld is a TIG type weld to melt the metal of both theflange and the bellows, to provide a complete seal between the flangeand the bellows. To complete the assembly process, neck portion 338 ofliner tube 318 is sized outward to cause a tight fit between neck 336and neck 338. Finally, a second weld is applied to the end edge of neck336 where it substantially aligns with the bend edge of neck 338.

A further pipe section may be welded to or formed on liner tube 318. Ina typical contemplated application of connector 310, the end of linertube 318 with lip 332 will be sized so that the outer diameter of lip332 is less than the diameter of the aperture of the pipe connector orhousing to which connector 310 will be attached.

Connector 310 may be affixed, such as by bolts 340 to a mating flange342 which may be connected, for example, to the exit pipe 344 of anexhaust manifold. Typically, flange 342 may be welded to or originallycast as part of the end of pipe 344. Flange 342 will have an internalaperture 346 which, as previously stated, will have an internal diameterwhich is greater than the external diameter of lip 332 of liner tube318, so that there will be some free clearance between lip 332 and theinner surface of aperture 346. This clearance is necessary, in order toaccommodate movement of lip 332 relative to the inner surface ofaperture 346.

Because the mechanical connection between liner tube 318 and flange 314is provided by the mesh ring 316, which is resilient and compressible,liner tube 318 will be capable of moving axially (as indicated by thedouble headed arrow A), laterally (as indicated by the double headedarrow B), and angularly (as indicated by the curved, double headed arrowC). Accordingly, connector 310 is capable of accommodating relativeaxial compression (which would be resiliently resisted by bellows 312),axial extension (which would be resiliently resisted by mesh ring 316)and angular movement (resiliently resisted by both bellows and meshring) of liner tube 318 relative to flange 314 and, in turn, relative toflange 342.

When connector 310 is assembled, it has an axial preload, so that bothbellows 312 and mesh ring 316 are slightly compressed. The spring forceof the bellows pulls on the liner tube and, in turn, compresses the meshring. It is contemplated that the environments in which the connectors310 will be used, the liner tube will be more often in tension than incompression, tending to keep the mesh ring in compression. Although somecompressive forces may be encountered by the liner tube, tending to pushthe lip and mesh ring away from the flange, preferably, the bellows willhave sufficient spring force that for ordinary operating conditions, themesh ring does not become completely unloaded.

FIG. 36 illustrates an alternative embodiment of the invention.

Connector 350 includes a liner tube 318' which has a cylindrical portion330' and a radially outwardly turned lip 332'. Flange 314' will have acentral aperture and one or more bolt holes like bolt hole 324'. Bellows312' will have necks 336' and 334' and will be provided with one or moreconvolutions. Connector 350 differs from connector 310 in that thecentral aperture of flange 314' has two distinct sections to it. Thefirst section having a small diameter portion 352 and a second portionhaving a substantially greater diameter 354. The larger diameter portion354 provides a notch in flange 314' for receiving a second mesh ring356. Unlike mesh ring 316', mesh ring 356 has an axial length which issubstantially less than its radial thickness. The radial thickness ofmesh ring 356 will be substantially greater than the radial thickness ofmesh ring 316'. In addition, the axial thickness of mesh ring 356 may bemore or less the same as the axial depth of the greater diameter portion354 of the central aperture of flange 314'. Since mesh ring 356 and meshring 316' will be directly abutting one another, it is believed thatbecause mesh ring 316' will be resting on a somewhat softer surface thanmesh ring 316 does in the embodiment of FIGS. 34 and 35, connector 350of FIG. 36 will have a somewhat greater degree of freedom in the axialextension, compression and angular movement which it may accommodate.

The construction of the connectors of the present invention have theadvantage of providing a substantially leak free connection which can beprovided, for example, at the flange of the exhaust manifold outlet pipein a package which is the same size or smaller than conventional balljoint type constructions. At the same time, the present inventionincorporates an improved construction with the reduced number of weldswhich, in turn, leads to a more simplified construction and a lessexpensive construction. The present connector construction also allowsfor a greater diameter of the passageway at the point of connection andthus leads to greater volumetric flow rates which can be obtained and,in turn, greater efficiency of the exhaust system.

In addition, by moving a portion of the liner tube actually into theoutlet of the exhaust manifold pipe, flow of exhaust gases is promptedinto the connector, further facilitating the flow. The positioning ofthe mesh ring(s) to positions upstream of the flange also have theeffect of shifting the "center" of the bending forces which the bellowsencounters, away from the axial midpoint of the bellows, as has been thecase in many prior art flexible exhaust connectors.

The foregoing embodiments describe and illustrate an end of the bellowspassing through the aperture in the flange plate, and employing a last,crushed convolution of the bellows as a seal between the manifoldhousing (or other structure) and the flange plate. As previouslymentioned, the formation of the bellows within the flange plate may beaccomplished through hydroforming techniques, as described in detailhereinabove, or by alternative methods, such as spin forming, etc.

In each of the foregoing embodiments, the mesh ring serves to partiallyshield the bellows from direct exposure to the full force andtemperature of the exhaust flow, although some, greatly slowed andreduced temperature leakage through the mesh ring, into the spacebetween the bellows and the pipe end, may occur. In this way, thebellows is protected from the full high temperature flow, lengtheningthe useful lifespan of the decoupler apparatus.

The foregoing description and drawings merely explain and illustrate theinvention and the invention is not limited thereto except insofar as theappended claims are so limited, as those skilled in the art who have thedisclosure before them will be able to make modifications and variationstherein without departing from the scope of the invention.

We claim:
 1. A vibration decoupling connector apparatus, for connectingfirst and second components of a fluid conduit system, comprising:amounting member, having an aperture therethrough for the passage offluid, the aperture having an inside peripheral surface, the mountingmember being configured for attachment to a structural member in a fluidconduit system; a liner tube member, having a first end and a secondend, the liner tube being insertably received through the aperture ofthe mounting member, so that the first end of the liner tube member isdistal to the mounting member and the second end of the liner tubemember is proximate to, and positioned on an opposite side of themounting member from the first end; a flexible resilient sealing member,substantially surrounding at least a portion of the liner tube memberand having two ends, a first of the two ends being sealingly connectedto the first end of the liner tube member, a second of the two endsbeing sealingly connected to the mounting member, at a positionproximate to the aperture of the mounting member; at least one annularvibration absorbing damping member circumferentially surrounding thesecond end of the liner tube member, a portion of the damping memberbeing radially positioned between a portion of the surface of themounting member adjacent the aperture and a portion of the liner tube, afirst axial face of the annular vibration absorbing damping member beingdisposed in axially abutting contact, at least indirectly, with a facesurface of the mounting member, the annular vibration absorbing dampingmember operably supporting at least a portion of the liner tube,relative to the mounting member, so that the liner tube may undergorestricted axial and angular movement relative to the mounting member; aperipheral lip on the second end of the liner tube member, forming acircumferentially extending annular region to insertingly receive aportion of the axial length of the at least one annular vibrationabsorbing damping member, and axially abut a second axial face of theannular vibration absorbing damping member, positioned opposite thefirst axial face of the annular vibration absorbing damping member, theflexible resilient sealing member being axially preloaded, to initially,axially prompt the liner tube member in a direction relative to themounting member, so that at least one annular vibration absorbingdamping member is, in turn, at least initially prompted toward themounting member.
 2. The vibration decoupling connector according toclaim 1, wherein the resilient sealing member is positionedsubstantially against the inside surface of the aperture.
 3. Thevibration decoupling connector according to claim 1, wherein themounting member comprises a substantially planar flange member and theinside surface of the mounting member comprises two portions, a firstportion having a first inside diameter, proximate a first axial face ofthe flange member and a second portion, having a second inside diametergreater than the first inside diameter, proximate a second axial face ofthe flange member,the face surface being axially abutted, at leastindirectly, by the annular vibration absorbing damping member, beingdisposed between the first and second portions of the inside surface ofthe aperture of the mounting member, the face surface, the secondportion of the inside surface of the aperture of the mounting member anda portion of the liner tube defining an annular pocket.
 4. The vibrationdecoupling connector according to claim 3, wherein the annular vibrationdamping member is partially received within the annular pocket.
 5. Thevibration decoupling connector according to claim 3, wherein the annularvibration damping member is fabricated from compressed metal meshmaterial.
 6. The vibration decoupling connector according to claim 3,further comprising a second annular vibration damping member is receivedwithin the annular pocket, and the first annular vibration dampingmember axially abuts the second annular vibration damping member.
 7. Thevibration decoupling connector according to claim 6, wherein at leastone of the first and second annular vibration damping members isfabricated from compressed metal mesh material.
 8. The vibrationdecoupling connector according to claim 1, wherein the resilient sealingmember comprises a bellows member having at least two annularconvolutions along its length.
 9. The vibration decoupling connectoraccording to claim 1, wherein the peripheral lip has a greatest outerdiameter that is less than an inner diameter of an aperture disposed inthe structural member of the fluid conduit system, the peripheral lipextending axially away from the mounting member, to extend into theaperture disposed in the structural member of the fluid conduit systemwhen the mounting member of the vibration decoupling connector isattached to the structural member.
 10. The vibration decouplingconnector according to claim 1, wherein the resilient sealing member andthe annular vibration absorbing damping member are both disposed inaxial compression, when the connector is in a neutral state and notencountering compressive, tensile or bending forces.
 11. The vibrationdecoupling connector according to claim 1, wherein the circumferentiallyextending annular region comprises an annular slot that insertinglyreceives and at least partially radially surrounds at least a portion ofthe axial length of the at least one annular vibration absorbing dampingmember.
 12. A vibration decoupling connector apparatus, for connectingfirst and second components of a fluid conduit system, comprising:amounting member, having an aperture therethrough for the passage offluid, the aperture having an inside peripheral surface, the mountingmember being configured for attachment to a structural member in a fluidconduit system; a liner tube member, having a first end and a secondend, the liner tube being insertably received through the aperture ofthe mounting member, so that the first end of the liner tube member isdistal to the mounting member and the second end of the liner tubemember is proximate to, and positioned on an opposite side of themounting member from the first end; a flexible resilient sealing member,substantially surrounding at least a portion of the liner tube memberand having two ends, a first of the two ends being sealingly connectedto the first end of the liner tube member, a second of the two endsbeing sealingly connected to the mounting member, proximate to theaperture of the mounting member; an annular vibration absorbing dampingmember circumferentially surrounding the second end of the liner tubemember, a portion of the damping member being radially positionedbetween a portion of the surface of the aperture and a portion of theliner tube, a first axial face of the annular vibration absorbingdamping member being disposed in axially abutting contact, at leastindirectly, with a face surface of the mounting member, the annularvibration absorbing damping member operably supporting the liner tube,relative to the mounting member, so that the liner tube may undergorestricted axial and angular movement relative to the mounting member; aperipheral lip on the second end of the liner tube member, operablyconfigured to insertingly receive a portion of the axial length of theannular vibration absorbing damping member, and axially abut a secondaxial face of the annular vibration absorbing damping member, positionedopposite the first axial face of the annular vibration absorbing dampingmember, wherein the peripheral lip has a greatest outer diameter that isless than an inner diameter of an aperture disposed in the structuralmember of the fluid conduit system, the peripheral lip extending axiallyaway from the mounting member, to extend into the aperture disposed inthe structural member of the fluid conduit system when the mountingmember of the vibration decoupling connector is attached to thestructural member.